Fuel Cycle Vision for CANDUby Al Rose
Boczar pointed out that the four main drivers for selecting a fuel cycle are resources, technology, waste and politics and that no single fuel cycle can be appropriate for all countries. Many countries have no uranium resources but may have abundant thorium. Capabilities for fuel fabrication, enrichment, reprocessing, enrichment and waste disposal vary from one country to the next and all of the above are subject to political as well as business agendas.
In Boczar's view, the CANDU system is the most flexible one available and can offer custom designed fuel cycles for whatever combination of factors affect any specific country.
The current gem in AECL's jewel box is the CANFLEX fuel bundle which is scheduled for a demonstration in Point Lepreau this year. CANFLEX is a modification of the standard CANDU fuel featuring two pin sizes and 43 elements rather than the current 37. A critical innovation involving a number of buttons attached to the pins improves the heat transfer properties of the bundle markedly. The key feature of this innovation is that it has been patented and AECL will receive royalties from any manufacture by customers, something that does not apply to the standard CANDU fuel.
CANFLEX will start with natural uranium fuel but the intention is to move to slightly enriched uranium, which can lower fuel cycle costs by as much as 30%, and then on to many combinations of fuel such as recycled light water reactor fuel, reconstituted weapons material, thorium etc. CANDU fuel can even be modified to burn actinides, which, in Boczar's opinion makes no technical sense but may be politically important.
In the long term Boczar said that the most compelling reason for CANDU to remain an important part of the international mix was a synergistic relationship to the LWR fuel cycle. He said that CANDU can burn spent LWR fuel directly or after processing by new methods that are proliferation resistant and therefor politically more acceptable. Boczar concluded by saying that the CANDU reactor, because of its inherent flexibility, is indispensable to any LWR system using recycling on either a national or regional basis.